1. Faulty Injector Driver: The injector driver is an electronic component responsible for controlling the opening and closing of the injectors. if it is faulty, it can lead to the absence of injector pulse.
2. Open or Short Circuit in the Wiring: Check the injector wiring for open circuits (broken wires) or short circuits (wires in contact with each other or conductive surfaces). Continuity tests can help identify such issues.
3. Faulty Engine Control Unit (ECU): The ECU controls various electrical components, including the fuel injectors. If the ECU is experiencing internal issues, it may not send injector pulse signals. Diagnosing ECU issues requires specialized tools and knowledge.
4. Fuel Pump Failure: If the fuel pump fails or is not functioning properly, there will be no fuel flow to the injectors, leading to no injector pulses.
5. Fuel Filter Clogging: A clogged fuel filter can restrict the fuel supply to the injectors, causing irregular or no injector pulses.
6. Low Fuel Pressure: If fuel pressure is too low due to a malfunctioning fuel pressure regulator or weak fuel pump, the injectors may not be able to function properly.
7. Sensors Issues: Various sensors, such as the Crankshaft Position Sensor and Camshaft Position Sensor, provide essential signals to the ECU for injector control. If these sensors are faulty, it can affect injector pulses.
8. Incorrect Wiring Connections: Check that all wiring connected to the injectors and the ECU is done according to the vehicle's wiring diagram. Any incorrect connections can impact the injector pulse signals.
9. Relay/Fuse Issues: Relays and fuses related to fuel injection can be checked to ensure they are functioning properly and supplying power to the injector circuit.
10. Immobiliser System Malfunction: Some vehicles have an immobiliser system that can prevent engine starting due to security reasons. if there is an issue with the immobiliser system, it can affect injector pulse signals.
It's recommended to have the vehicle inspected by a qualified mechanic who has experience in diagnosing electrical and fuel injection system issues. They will be able to identify the root cause of the problem and carry out the necessary repairs to restore the injector pulses and resolve the service engine soon light condition.
